Author
Topic: The 2018/2019 freezing season (Read 256726 times)

Yes, snow is an insulator. However, that does mean that the ground is on fire beneath it. The land will lose heat to the air (not space), dependent on the temperature gradient. Given enough time, the land surface and air will reach an equilibrium. A layer of snow will slow down the rate of heat transfer. The same layer that prevents cooling at night, prevents heating during the day (where the sun is shining). Soil moisture has the same effect. Hence, at identical temperatures, pipes will freeze slower when snow is present, and proportional to its thickness. Eventually, those pipes will freeze also.

magnamentis

even though i don't think this is a serious question, i'l gladly answer it:

a) permanent extreme as well as too long term forecasts

b) swiss cheese greenland ice-shield

c) new ice age

and not willing to learn the tiniest bit and moderate the terminology and to throw in theories and ideas more for consideration and/or as questions instead like statements of facts.

i tried 2 years to hint at the possibility to be less extreme, less absolute, less resolute and then you changed the topics of interest various times, from extent to greenland cheese to snow cover and it each instance the statements were definitely far off or jumping to conclusions from one season or one month of events to the next millions of years.

i hope you keep your promise to take a brake, shall i say; mission accomplished ? LOL

The specific heat of rock/soil is significant. For granite it is about 20% of that of water by weight. But granite is 2.75 x the density of water, so over 50% of the heat capacity of water. The soil and rock below us cannot absorb as much water as the ocean, but it still can absorb quite a lot. The importance of the ocean's ability to absorb heat is not just its specific heat capacity, but the rate that the heat can mix down below the surface (and then mix back up again). In contrast the soil and rock pretty much does not mix up or down except in very unusual circumstances, and heat can only move in or out through conduction, and not be convection.

Heat absorbed by the ground can have quite a significant impact on weather as the Brown Ocean effect

Logged

Climate change: Prepare for the worst, hope for the best, expect the middle.

...... the 2016-2018 sea ice extent gap ripped open further, now to almost 1.5 million square kilometers. Most of the sea ice gap ripping was due to the present High Arctic & Arctic atmospheric chilling, funneling from Canada. However, the extreme to-date 2016 anomalous heating also caused sea ice extent LOSS, contributing to the wild splaying 2016-2018 sea ice extent separation. Should be more 2016-2018 sea ice extent widening coming.

The last fews days have placed the first (& largest) to-date 2016 sea ice extent LOSS in this general time of sea ice extent gain, graphically in the past. 2018 sea ice extent gain is presently paralleling the 2016 sea ice extent gain, but 1.5+ million square kilometers greater. Present High Arctic temperature is somewhat lower than the same period 2016 High Arctic temperature, possibly helping to maintain the 2016-2018 Arctic sea ice gap.

Since the recent greatest "2018-2016 Arctic sea ice extent" gap of 1.5+ million square kilometers, the gap has been decreasing, now to just 1.0+ million square kilometers. Present 2018 High Arctic atmospheric temperatures aren't as high as the same period in 2016, which would NOT explain the present narrowing between 2018 & 2016.

...In contrast the soil and rock pretty much does not mix up or down except in very unusual circumstances, and heat can only move in or out through conduction, and not be convection....

It makes the math much more simple for a single profile. Conduction is easy to model. In contrast, across regions, modelling is much more difficult as there are enormous lateral variations. The grounds organic material, composition,layer structure, and water content all have to be accounted for. That and the way vegetation changes snow coverage makes predicting globally a challenge. At least in the oceans we just have heat and salinity...

It does mean that the depth when there is very little yearly variation is easy to find. I think it's about 2-3 meters for a decent wine cellar in Oxford.

It makes me shiver [freezing season, so on topic??] to think I grew up with the two Flanders & Swann records, including, of course, the Hippopotamus Song (words include "... let us wallow …"). By chance, I met Donald Swann at the Quaker Meeting in Johannesburg, South Africa, where he, also, was visiting.

Interesting to see how the entire Atlantic front is pushed back in the last two frames. There was a low pressure area south-east of Svalbard that is now in decline, but the winds seem to have been mostly from east-north-east.

« Last Edit: November 30, 2018, 09:16:13 AM by binntho »

Logged

because a thing is eloquently expressed it should not be taken to be as necessarily trueSt. Augustine, Confessions V, 6

The extent numbers look quite healthy so far, but thicker ice is still melting along the Atlantic front all the way to FJL and looks like it will continue to melt for a while longer in the Chukchi. Fram/NSvalbard export may make a bigger difference this freezing season.jaxa 2018 and 2017, nov1-30

A closer look at the Atlantic ice front using amsr2-uhh and comparing with mercator temperatures 0m and 34m depth. The mercator model showing most of the warmer Atlantic water flowing east towards Novaya Zemlya, with a smaller current flowing north towards Svalbard then turning east towards FJL along the edge of the Nansen basin.If I understand correctly, some of the warmer salty atlantic water will mix with fresher melt water in the choppy seas along the ice front but most is destined to sink into the depths of the Nansen basin, the salt making it denser, despite being warmer.

Notice how the thinner ice north of FJL melts even when blown northward onto the warmer current.

amsr2-uhh, mercator temperature 0m and 34m, nov1-dec1

edit: Lower concentration ice is still just discernible over the 'upwelling' north of Svalbard.

edit: Some further detail on currents in the Fram Srait from a recent paper:

Quote

Fram Strait is the northernmost extension of the northern North Atlantic, and is the only deep gateway to the Arctic Ocean. The eastern Fram Strait is characterized by the West Spitsbergen Current carrying warm Atlantic Water northwards along the shelf-break ( Fahrbach et al., 2001;Schauer and BeszczynskaMöller, 2009;Beszczynska-Möller et al., 2012), continuing eastwards on the northern side of Svalbard (Figure 1). The current system west of Svalbard is complex and consists of three branches (Nilsen et al., 2016); an inner branch (the easternmost) crossing the Yermak Plateau, a branch following the western rim of the Yermak Plateau, and an offshore branch often called the Return Atlantic Current going further offshore and sending filaments of Atlantic Water westwards across Fram Strait.https://tinyurl.com/y9cf8lqxKnutsen, Tor & Wiebe, Peter & Gjøsæter, Harald & Ingvaldsen, Randi & Lien, Gunnar. (2017). High Latitude Epipelagic and Mesopelagic Scattering Layers - A Reference for Future Arctic Ecosystem Change. Frontiers in Marine Science. 4. 10.3389/fmars.2017.00334.

Still way to far out. There were lots of forecasts last fall that suggested all kinds of dire stuff - worse for ice creation than 2016 - but which moderated dramatically when we got closer to the 4 day window. What you are seeing at day 8 is still so general and has such high probability of error that it has little utility beyond tweaking our curiosity.

All ensembles are also in agreement. This is partially due to the recurving WPAC storm / typhoon which becomes a major low near AK. I think this leads to a higher probability forecast vs. normal. But if I am wrong, feel free to throw this in my face come D8 (I will post verification then, myself!).

2011 is another comparative year to this year and what happened in 2012?Any chance you can do the comparative map between 2011 and 2018?

2011 at this stage was very much different. Much less atlantification and pacification (ie. more ice in Bering/Chukchi, Barents) and much less ice in the Hudson.

The current setup (and probably the future) is more and more Atlantification and Pacification which leads to open seas at quite high latitudes. This leads to low pressure systems "curving" the jetstream and - as someone put it quite well on this forum - the cold comes out like from a toothpaste tube on the two ends, leading to a quick refreeze of the Hudson (making bbr very happy

In fact, the only years quite similar to this one (open Bering, Chukchi, Barents and freezing Hudson) are the Decembers of 2007, 2013,15,17.

It seems to me that this setup is becoming the norm. I attach the 2007 and 2011 comparisons.

I think the most important thing is the thickness in the CAB and directly surrounding regions, as this sets the resilience to withstand the melting season. The max is relatively meaningless, especially the Okhotsk and St. Lawrence parts as they are completely disconnected, and Baffin as well due to its southbound currents. The Greenland Sea matters only in its very northern parts, as the rest has a strong current flowing south.Only the Barents/CAB region is very important, indicating the level of Atlantification that also strongly affects the melting season, and to a lesser degree the Bering indicating Pacification.Note the Kara freezes up completely every year and is irrelevant as far as the max goes.

Chukchi might be icing over in the next week or two if the GFS extended forecast holds decently true.

The GFS *always* overestimates cold over the highly saline SSTs up north, and does the inverse for the fresh SSTs to their south (Kara, HB). I would be this is another false alarm. The model bias is systemic and incorrigible...!

Warm and salty water remains historically encroached on the Arctic on both the Atlantic and Pacific front. Very bad news. Anywhere that doesn't have this true "ocean" water will obviously freeze while the sun is away. The question seems to be how much depth/power does the Pacific water in the Chukchi have. We might get a hint in during the next month, but won't get a definative answer until next April.

The shrinking distance between the encroaching salty oceans is the most noteworthy thing going on in the global climate system.

Since the recent greatest "2018-2016 Arctic sea ice extent" gap of 1.5+ million square kilometers, the gap has been decreasing, now to just 1.0+ million square kilometers. Present 2018 High Arctic atmospheric temperatures aren't as high as the same period in 2016, which would NOT explain the present narrowing between 2018 & 2016.

2018 Arctic sea ice extent has reduced to the level of the average of the 2010's AND continues reducing the gap to 2016, now only ~ 0.6 million square kilometers greater.

The cold Canadian weather at this time last year & through the winter was fairly stable. This year Canada again started stable for the first month of anomalously low Canadian fall temperatures. But the Canadian cold has been moving the last month or so, sometimes into the U.S. & sometimes even into the High Arctic. Recently some warm fronts proceeding from Siberia & Alaska have been pushing into the High Arctic. But High Arctic temperatures are not jumping sky high, because the cold fronts from Canada have also been drifting into the High Arctic.

Logged

magnamentis

Since the recent greatest "2018-2016 Arctic sea ice extent" gap of 1.5+ million square kilometers, the gap has been decreasing, now to just 1.0+ million square kilometers. Present 2018 High Arctic atmospheric temperatures aren't as high as the same period in 2016, which would NOT explain the present narrowing between 2018 & 2016.

2018 Arctic sea ice extent has reduced to the level of the average of the 2010's AND continues reducing the gap to 2016, now only ~ 0.6 million square kilometers greater.

considering all the obvious information more or less all the stalls in freezing or even short dives are wind and wave action related.

whenever the whether is calm or relatively calm ice is building steadily and as soon high winds and the related waves come up from southerly regions at speed on both sides of the arctic things start to change to the worse.

temps alone, even while 20C above norm, if those 20C above norma are -20C the impact on the ice extent growth is negligible but above average temps + warm waters stored in depth + high winds and waves triggered such events repeatedly IMO

this is a very general observation or let's say "impression" to remain careful but to me that's how it looks.

A reminder that warmer salty water tends to sink below colder fresh water. The atlantic side has a stronger current/larger incoming volume than the pacific but both tend to be limited in 'encroachment' by the depth of the arctic ocean (or sea or estuary).At this stage it would appear that the ice gets thinner while attempting to cover historical extent.

Since the recent greatest "2018-2016 Arctic sea ice extent" gap of 1.5+ million square kilometers, the gap has been decreasing, now to just 1.0+ million square kilometers. Present 2018 High Arctic atmospheric temperatures aren't as high as the same period in 2016, which would NOT explain the present narrowing between 2018 & 2016.

2018 Arctic sea ice extent has reduced to the level of the average of the 2010's AND continues reducing the gap to 2016, now only ~ 0.6 million square kilometers greater.

....temps alone, even while 20C above norm, if those 20C above norma(sic) are -20C the impact on the ice extent growth is negligible......

First, I've always referred to no local temperatures outside the High Arctic. My references have always been of average temperatures over the High Arctic which is almost 4 million square miles surrounding the North Pole. Second, since you mention 20C above normal while referring to my posts, you must mean the 2016 early December anomalous temperature. During this anomalous 20degC above average temp event over 4 million square miles surrounding the North Pole, it was NOT -20degC. The actual temperature was -7degC., again, averaged over 4 million square miles surrounding the North Pole. Third, while the average temperature over 4 million square miles around the North Pole was -7degC, thawing regional temperatures 700 miles(& greater?) to the south, outside the High Arctic were occurring AND did reduce Arctic sea ice extent. To state that such vast heats in the Arctic negligibly impact Arctic sea ice growth, specially in the instance that you need major correction of the true temperature AND areas affected, truly casts your allegation aside. Fourth, your consideration that VAST High Arctic temperature rises (erroneous in two ways, on your part) are only coincidentally timed to minimal sea ice growth, AND even to Arctic sea ice LOSSES(NOT mentioned by you), during usual times of vast Arctic sea ice gains, must be thought little researched by you.

A comparison of Atlantic side using amsr2-uhh, nov1-dec4, 2018,2017,2016,2015.2015 is missing a couple of frames due to poor data so the day before was duplicated. Date label is too small. edit:bigger date for 2018

magnamentis

First, I've always referred to no local temperatures outside the High Arctic. My references have always been of average temperatures over the High Arctic which is almost 4 million square miles surrounding the North Pole. Second, since you mention 20C above normal while referring to my posts, you must mean the 2016 early December anomalous temperature.

there must be a big misunderstanding and i assume it's my fault even though i'm not aware what it was that make you think that i denied anything you wrote.

i simply wanted to point at the correlation between wind and wave action as a main driver for unusual plateaus and/or dips in ice-building and for the rest i'm totally in agreement with what you pointed out.

the 20C were an example, i thought that i wrote "i.e" hence all the explanation you made dropped on already planted earth not the tiniest bit of disagreement, simply added one point to all your correct points.

thing is that i predicted a plateau about a month ago but thought it would happen earlier and not that pronounced. in the aftermath when it didn't happen i started to search differences between when unusual dips and plateaus happen and when not, and came to the conclusion that the difference is mostly warm and moist air carried north by mostly atlantic but also pacific storms that at the same time stir up the seas and mix the layers, kind of dig up warmer and perhaps more saline waters.

The Kara ice was thrown back big time, which explains the sharp extent slowdown/contraction. Once this process stops, Kara will have room for quick growth again, in addition to Hudson, and we will have another period of above average gains.

Eventually HB and Kara will freeze - but all forecasts seem to agree on more of the same, temps way above average over both areas, with southerlies particularly strong over Kara but also significant over the Hudson.

So the race is on for the end of month ranking!

Logged

because a thing is eloquently expressed it should not be taken to be as necessarily trueSt. Augustine, Confessions V, 6

Eventually HB and Kara will freeze - but all forecasts seem to agree on more of the same, temps way above average over both areas, with southerlies particularly strong over Kara but also significant over the Hudson.

Eventually HB and Kara will freeze - but all forecasts seem to agree on more of the same, temps way above average over both areas, with southerlies particularly strong over Kara but also significant over the Hudson.

So the race is on for the end of month ranking!

Ya its really warm over Hudson Bay...

Were you thinking of flying there in a balloon? I've never understood your fixation with the 850Hp temperature, that's not where the ice freezes, but 1.5 km further down. But, yes, it is bloody cold in the Hudson at the moment and freezing has picked up again.

I was, on the other hand, talking generally about the forecast, and looking at the anomaly and starting this coming Sunday the forecast is for large and increasing anomalies over the Hudson Bay, but perhaps more importantly, southerly winds and even a small low-pressure area building up over the southern HB if Windy.com is to be trusted.

So above-average temparatures, southerly winds and wave action within the next few days and apparently continuing as far as the forecasters dare to cast their fores.

Logged

because a thing is eloquently expressed it should not be taken to be as necessarily trueSt. Augustine, Confessions V, 6

Actually, The Atlatic Front is very warm now (as shown on the first pic, ecmwf todays 850 hpa temp anomaly, red: hot, blue: cold) but this will change, and North America will warm up (second pic, ecmwf t+6 days 850 hpa temp anomaly). Third pic: same as second, but only North America shown.

So the Hudson will probably be (relatively) quite warm in a few days' time and the Atlantic Front will "normalize"

Worldview, viirs brightness temperature band15, night, dec6. https://tinyurl.com/y7s5h2hfGreenland Sea looking a bit worse for wear after another storm and thick(ish) ice lined up for Fram export.edit: Nares still open. That large floe rounding off its edges as it goes down.

Agreed, patches of flash freezing already visible.... but the pack is so mobile, looking a bit wounded almost (obviously I'm reading too much into it )ascat, last 20days (enhanced contrast,clahe,unsharpmask)

A more detailed look at the mobile ice in the CAB, north of ESS/Chukchi, dec7-8. Mostly lots of small fractures. - On average (last 10 years) 65.9 % of the increase in extent from min to max is done.Accepted that the CAB may thicken for a while longer.